In U.S. Pat. No. 3,869,268, assigned to the assignee of the present invention and incorporated herein by reference, a method and apparatus for chopping glass strands is disclosed. The apparatus includes a roll having a plurality of cutting blades embedded therein and a backup roll having a resilient surface such that when glass strand passes between the two rolls, glass strand is chopped therebetween. The apparatus further includes a feed roll formed of a nonresilient material, such as stainless steel, in contact with the backup roll. The combination of these two rolls provides the attenuation forces necessary to attenuate continuous glass strand from bushing tips in a bushing to provide the source of glass strand for the chopping operation. In this patent, the feed roll is disclosed as having a knurled surface to provide the necessary tractive force between the glass strand and the two rolls.
There is a problem associated with the feed roll of the prior art. As the glass strand is attenuated, it is coated with a binder and/or size. The wet glass strand is then passed between the feed roll and the backup roll. The binder and/or size readily accumulates in the knurled surface of the feed roll thus quickly forming a smooth surface on the feed roll. When this occurs, the glass strand tends to wrap around the feed roll rather than continuing between the backup roll and the cutting roll. This stops the continuous formation of chopped glass strand and adversely affects production due to the time required to unravel the strand and clean or replace the feed roll. It is desirable, therefore, to provide a feed roll which prevents the problems associated with the prior art system from occurring during processing.